Reasons WCDMA cells send handover preparation failure messages to EUTRAN

Hello Experts.
What reasons would WCDMA cells send handover preparation failure messages to EUTRAN?
I have an issue with L.RATHO.E2W.prep.FailOut.Prepfailure.
Huawei network.

Wrong external 3G cell define or 3G cell resource congested.

Hi @proberbs31,
If HO due to preparation, most probably some data definition missmatch between source and target…so most of the time failure rate will be 100% …
so just double then…

good luck

1 Like

All the cells are diffined correctly, including frequencies and priorities.
Recheck the CSFB parameters. CSFB is activated, blind handover on at both eNodeB and Cell level. Priority is 32.
MT won’t get ring despite MO having ring sound.
It’s intermittent.

Check redirection switch and check if csfb is rscp or ecno based.
It may be aggressive values so mt failing.
And for lrat prep fail may be in eNodeB ultraflashcsfb is on.

Having issue with L.IRATHO.E2W.SRVCC.Prep.FailOut.PrepFailure.
Any suggestions?

Tell us what actions you did up till now from configuration to optimization.
So that we can get an idea what is missed
It’s a very generic question…

SRVCC at eNB may trigger for CS+PS.
Please check 3G Core + RAN support preparation for CS+PS simultaneous or just CS…